A known approach to advanced technology fabrication of materials such as semiconductor substrates is to assemble a manufacturing facility as a “cleanroom.” In such cleanrooms, processing tools are arranged to provide aisle space for human operators or automation equipment. Exemplary cleanroom design is described in: “Cleanroom Design, Second Edition,” edited by W. Whyte, published by John Wiley & Sons, 1999, ISBN 0-471-94204-9, (herein after referred to as “the Whyte text” and the content of which is included for reference in its entirety).
Cleanroom design has evolved over time to include locating processing stations within clean hoods. Vertical unidirectional airflow can be directed through a raised floor, with separate cores for the tools and aisles. It is also known to have specialized mini-environments which surround only a processing tool for added space cleanliness. Another known approach includes the “ballroom” approach, wherein tools, operators and automation all reside in the same cleanroom.
Evolutionary improvements have enabled higher yields and the production of devices with smaller geometries. However, known cleanroom design has disadvantages and limitations.
For example, as the size of tools has increased and the dimensions of cleanrooms have increased, the volume of cleanspace that is controlled has concomitantly increased. As a result, the cost of building the cleanspace, and the cost of maintaining the cleanliness of such cleanspace, has increased considerably.
Tool installation in a cleanroom can be difficult. The initial “fit up” of a “fab” with tools, when the floor space is relatively empty, can be relatively straightforward. However, as tools are put in place and a fabricator begins to process substrates, it can become increasingly difficult and disruptive of job flow, to either place new tools or remove old ones. Likewise it has been difficult to remove a sub-assembly or component that makes up a fabricator tool in order to perform maintenance or replace such a subassembly or component of the fabricator tool. It would be desirable therefore to reduce installation difficulties attendant to dense tool placement while still maintaining such density, since denser tool placement otherwise affords substantial economic advantages relating to cleanroom construction and maintenance.
There are many types of manufacturing flows and varied types of substrates that may be operated effectively in the mentioned novel cleanspace environments. It would be desirable to define standard methodology of design and use of standard componentry strategies that would be useful for manufacturing flows of various different types; especially where such flows are currently operated in non-cleanroom environments.
In many types of substrate processing environments, a common and important processing step may include “lithography” processing where images are imparted to films of sensitive material upon the substrate. In the state of the art optical lithography is used to impart images through lithography masks. In other embodiments, electron beams are used to impart images in a controllable fashion. There may utility for creating systems where imaging systems may be formed with large parallel combinations of imaging elements that process a full substrate simultaneously. Such imaging elements that process a full substrate simultaneously may also be consistent with the desire to reduce installation difficulties for processing tools as previously mentioned.